Known is a stereocamera in which two image capturers are fixed to one casing to capture the same subject with the left and right image capturers. The stereocamera captures the subject from a plurality of different directions and records plane-direction information and depth-direction information (three-dimensional information).
As a device reconstructing the three-dimensional information, known is a three-dimensional information reconstraction device that includes, for example, an image input, a corresponding point detector, an elementary matrix calculator, a translation calculator, a rotation calculator, and a distance calculator (refer to, for example, PTL 1).
In the three-dimensional information reconstraction device, the image input inputs two images of a captured three-dimensional rigid body. The corresponding point detector detects corresponding points between the two images. The elementary matrix calculator calculates an elementary, matrix from a three-dimensional rotation matrix and a three-dimensional translation vector between the two images. The translation calculator calculates the three-dimensional translation vector. The rotation calculator calculates the three-dimensional rotation matrix. The distance calculator calculates the distance between the camera and the corresponding point in a three-dimensional space.
However, in the case of forming a stereocamera system by individually installing two image capturing devices, the three-dimensional coordinates of a target point may not be correctly restored from left and right images that are respectively captured by the two image capturing devices.
Specifically, for example, the three-dimensional coordinates may not be correctly restored in the case of a small number of corresponding points that represent a positional relationship of corresponding feature points between images of each captured image, or in the case of feature points extracted from each captured image being concentrated in a specific position on the images.
An object of the present disclosure is to improve reconstraction accuracy for three-dimensional coordinates restored from two captured images.